BEIJING -- Beijing has invited overseas investment to help solve environmental pollution and other problems plaguing the capital, according to a vice mayor.

"We're fighting a hard battle against urban ills," vice mayor Cheng Hong said on Wednesday, addressing an audience of chamber of commerce representatives.

Investment is preferred in fields such as water use and management, air pollution control, as well as intelligent transportation, Cheng said.

With a permanent population of more than 20 million, Beijing is plagued by severe air pollution and traffic congestion.

"Many transnational companies boast rich experience in coping with waste water and air pollution," she said, pledging to improve the city's investment environment.

Government data shows from January to October, Beijing utilized $8.23 billion of overseas investment.